An inkjet-recording device includes a recording head with a plurality of juxtaposed nozzles. A recording paper is conveyed below the recording head while the recording head forms an image on the paper. The recording head records an image on the recording paper by moving in a main scanning direction (orthogonal to the paper-conveying direction), while ejecting ink droplets from the nozzles at a prescribed timing. In recent years, inkjet-recording devices have been provided with a photo printing function. This type of image recording is called “borderless recording” because the image is recorded without leaving margins on the edges of the recording paper.
In borderless recording, the recording head is moved beyond the edges of the paper and ink is ejected to a point outside the region occupied by the recording paper. For example, in Japanese unexamined patent application publication No. 2000-118058, when borderless recording is performed on the leading and trailing edges of the recording paper, the recording paper is positioned relative to the recording head so that a portion of the nozzles in the recording head is positioned off the edge of the recording paper. Consequently, the recording head ejects ink droplets through these nozzles onto a platen provided below the recording paper. The platen is provided with a groove formed in the top portion thereof and extending in the main scanning direction, and an ink absorbing material disposed inside this groove for absorbing the ink droplets. This configuration makes it possible to record an image over the entire recording paper, without leaving a border along the edges of the recording paper, while preventing ink ejected onto the platen from staining the underside of the recording paper.
There has also been a demand in recent years for inkjet-recording devices capable of recording images at a faster rate. Conventional attempts to increase the image recording speed have involved increasing the size of the recording head in order to increase the number of nozzles arranged in the paper-conveying direction. However, in order to perform high-quality borderless recording, it has been necessary to increase the width (dimension in the paper-conveying direction) of the groove provided in the platen as the size of the recording head is increased.
However, since the recording paper is positioned above this groove when performing borderless recording, an increased groove width may cause the recording paper to deform, bending downward into the groove. Such bending of the recording paper changes the distances between nozzles in the recording head and the surface of the recording paper, potentially leading to recording problems.
To resolve this problem, Japanese unexamined patent application publications Nos. 2001-80145 and 2002-307769 proposed providing paper support members in the groove formed in the platen. These paper support members rotate along with the recording paper as the recording paper is conveyed. The paper support members support the recording paper advancing over the groove, while moving in the width direction of the groove. Hence, the paper support members can support the recording paper when the recording paper is conveyed over the groove formed in the platen.